1. Field of the Invention
The present invention relates to a wire saw, and more particularly to a wire saw which slices brittle material (workpiece) such as silicon, glass and ceramics into a number of wafers.
2. Description of Related Art
A wire saw which slices a silicon ingot into wafers winds a wire on a plurality of grooved rollers to form a wire row between the grooved rollers. The ingot is pressed against the running wire row to be sliced into a number of wafers in one cutting action. The wire saw is constructed in such a way that an opening for loading and unloading the ingot is formed at the side of a cover, which covers the processing chamber where the grooved rollers are arranged. The cover is provided with a lid for opening and closing the opening.
FIG. 6 is a plan view showing the state wherein the above-mentioned wire saws A-F are arranged in three rows of two in a plant 1. In this case, the No. 1 wire saw A and the No. 4 wire saw D exchange the ingots in a space G enclosed by long and two short alternate lines. The No. 2 wire saw and the No. 5 wire saw E exchange the ingots in a space H enclosed by long and two short alternate lines. The No. 3 wire saw C and the No. 6 wire saw F exchange the ingots in a space I enclosed by long and two short alternate lines.
The above-mentioned wire saw, however, is constructed in such a way that the opening for loading and unloading the ingot is formed at the side of the cover. For this reason, while the No. 1 wire saw A is exchanging the ingots for example, the No. 4 wire saw D could not exchange the ingots. This is very inefficient.
To solve the above-mentioned problem, the plant 1 as a whole must be widened to increase the exchange spaces G-I.